1. Field of the Invention
This invention relates to a tying machine, more particularly to a tying machine which is operable manually.
2. Description of the Related Art
FIGS. 1 and 2 show a typical tying machine 10 which includes a base body 11, a wire reel 12 mounted on the base body 11 and carrying a wire 20, a support plate 13 disposed at the front of the base body 11 and having a recess 131, and a control switch 14 mounted on the support plate 13, a driving unit 15, an advancing unit 16, a cutting unit 17 and a tying mechanism 18.
The driving unit 15 includes a shaft 152 extending through the support plate 13 and driven by a motor 151, first and second gear discs 153, 154 sleeved around the shaft 152 beneath the support plate 13, a first gearwheel 155 disposed at the bottom side of the support plate 13 and driven by the first gear disc 153, a second gear wheel 156 engaging the first gear wheel 155, a bevel gear assembly 157 passing through the support plate 13 and driven by the second gear disc 154, and a drive wheel 158 mounted on the bevel gear assembly 157.
When the motor 151 is energized, a wire twisting unit 183 of the tying mechanism 18 is driven by the second gear disc 154, an advancing wheel 163 is driven through the second gear wheel 155 to advance the wire 20, and a rotary cam 171 is driven through the shaft 152 to actuate a link 172 so that a hook-like arm 173 is rotated to push the wire 20 to the recess 131. When the rotary cam 171 is rotated, the projecting part thereof pushes a roller 177, and a transmission rod 175 is driven to turn a transverse link 176 which in turn pushes a cutter 179 toward the wire 20 to cut the same. At the same time, the hook-like arm 173 is continuously rotated to cause the wire 20 to surround a bag (not shown) received by the recess 131. Finally, two ends of the cut wire 20 are moved into twisting grooves 182 of the wire twisting unit 183 and are then twisted by the wire twisting unit 183 to tie the opening of the bag.
Although the aforesaid tying machine 10 can achieve its intended functions, it encounters a problem in that malfunctions that occur during the operation of the tying machine is difficult to rectify, because reversal of the operations of the components which are driven by the motor 151 is not easy.